Process Overview

The thermal volume reduction system (TVR) consists of five major subsystems:

• Waste storage arrangement
• Feeding system
• High temperature reactor/boiler and energy recovery system
• Flue gas cleaning system
• Ash handling system

The feeding subsystem includes several hydraulic actuators that control the feedrate for various sections of the high temperature reactor/boiler. Each hydraulic actuator is controlled by the process control system. The control system then adjusts each hydraulic cylinder stroke and speed, as result, the waste feedrate is optimized.

Waste processing occurs in a high temperature (over 850°C) reactor/boiler via a reciprocating grate system consisting of high alloy steel casing grates (thus air cooling is sufficient). Each high temperature reactor/boiler (offered in 250 TPD modules) is capable of producing approximately 50 tons/hour of steam (450°C) at 3.82 MPa (assumed calorific value of 2,800 kcal/kg). During processing, municipal solid waste (MSW) is moved along the three sections of the grated area. The first section dries the MSW, while the second section oxidizes the MSW and the third section cools the remaining material to reduce the temperature of the ash and allows the system to recover some residual heat. The heat generated is converted into electricity via an energy recovery system consisting of a steam generator (boiler with 75% efficiency), steam turbine, power generator, water treatment system and heat exchanger.

Any fly ash generated in the thermal volume reduction system is transferred to a PTDR System where it is melted and reformed into a vitrified matrix product. Applications for this vitrified matrix product include roadbed/fill construction and concrete aggregate.